Can't figure out how to get my offset function to work correctly in VBA

The code works great fills in all the values. Problem is I'm already offsetting to get my "number1" but I need to offset "DIA" at the same time to get it to stay with the "number1".

Basically I need to select two different cells and have them offset one cell down at a time together.

Sub calctest()
Dim number1 As Double
Dim number2 As Double
Dim answer As Double
Dim SFM As Integer
Dim RPM As Double
Dim MAX As Integer
Dim ALPHA As Integer
Dim DIA As Double

SFM = InputBox("What is the SFM?")
ALPHA = InputBox("What Alpha symbol are you using?")
MAX = InputBox("What is maximum RPM for machine?")
DIA = Range("b23").Value

Sheets("Feeds and Diameters").Select

If ALPHA = 1 Then
ALPHA = Range("d23").Select
ElseIf ALPHA = 2 Then
ALPHA = Range("e23").Select
ElseIf ALPHA = 3 Then
ALPHA = Range("f23").Select
ElseIf ALPHA = 4 Then
ALPHA = Range("g23").Select
ElseIf ALPHA = 5 Then
ALPHA = Range("h23").Select
ElseIf ALPHA = 6 Then
ALPHA = Range("i23").Select
ElseIf ALPHA = 7 Then
ALPHA = Range("j23").Select
ElseIf ALPHA = 8 Then
ALPHA = Range("k23").Select
End If

Do Until Selection.Offset(0, -2).Value = ""

RPM = SFM * 3.82 / DIA
If RPM > MAX Then
RPM = MAX
Else
RPM = RPM
End If
    
number1 = Selection.Value
number2 = Round(RPM, 0)

answer = number1 * number2

Selection.Offset(0, 13).Value = Round(answer, 1)

Selection.Offset(1, 0).Select
Loop

End Sub

I am soooo close to my desired outcome, feel free to ask any questions.
I can send over the file I'm working on if interested as well

Dustin S.,

What is the sheetname where DIA is getting its value?

In the next loop, shoud DIA get its next value from Range("b24")?


Have a great day,
Stan

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Dustin S.,

Please TEST this FIRST in a COPY of your workbook (always make a backup copy before trying new code, you never know what you might lose).

Option Explicit
Sub calctest()
Dim number1 As Double, number2 As Double, answer As Double, RPM As Double, DIA As Double
Dim SFM As Integer, MAX As Integer, ALPHA As Integer
Dim NR As Long

SFM = InputBox("What is the SFM?")
ALPHA = InputBox("What Alpha symbol are you using?")
MAX = InputBox("What is maximum RPM for machine?")


NR = 23
DIA = Sheets("Feeds and Diameters").Range("B" & NR).Value

Sheets("Feeds and Diameters").Select

If ALPHA = 1 Then
  ALPHA = Range("d23").Select
ElseIf ALPHA = 2 Then
  ALPHA = Range("e23").Select
ElseIf ALPHA = 3 Then
  ALPHA = Range("f23").Select
ElseIf ALPHA = 4 Then
  ALPHA = Range("g23").Select
ElseIf ALPHA = 5 Then
  ALPHA = Range("h23").Select
ElseIf ALPHA = 6 Then
  ALPHA = Range("i23").Select
ElseIf ALPHA = 7 Then
  ALPHA = Range("j23").Select
ElseIf ALPHA = 8 Then
  ALPHA = Range("k23").Select
End If

Do Until Selection.Offset(0, -2).Value = ""

  RPM = SFM * 3.82 / DIA
  If RPM > MAX Then
  RPM = MAX
  Else
  RPM = RPM
  End If
      
  number1 = Selection.Value
  number2 = Round(RPM, 0)
  
  answer = number1 * number2
  
  Selection.Offset(0, 13).Value = Round(answer, 1)
  
  Selection.Offset(1, 0).Select
  
  NR = NR + 1
  DIA = Sheets("Feeds and Diameters").Range("B" & NR).Value
  
Loop

End Sub

Have a great day,
Stan

Dustin S.,

Would it be too much to ask what all you changed and why?

You wanted to get the value for "DIA" from B23, down.

' I created a variable NR, next row
Dim NR As Long

' And set it 23, starting row number 23 from your original code
NR = 23

' Then we loaded "DIA" from Sheets("Feeds and Diameters").Range("B23")
DIA = Sheets("Feeds and Diameters").Range("B" & NR).Value


' We had to use the "Sheets("Feeds and Diameters").Range....) because of 
'  the next code statement for your loop.
Sheets("Feeds and Diameters").Select


  ' Then at the bottom of your loop I added 1 to NR
  NR = NR + 1
  
  ' Then we loaded "DIA" from the next row, B24, and so on for each pass of your loop
  DIA = Sheets("Feeds and Diameters").Range("B" & NR).Value

Have a great day,
Stan